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<H1>contains(+Map, ++Key)</H1>
Check whether a map contains a key.
<DL>
<DT><EM>Map</EM></DT>
<DD>A map
</DD>
<DT><EM>Key</EM></DT>
<DD>The key to look for
</DD>
</DL>
<H2>Description</H2>
	<P>
	This predicate checks the map Map to see whether it contains an
	entry with key Key.
	</P>
	<P>
	This predicate should only be called with maps created by other
	predicates from the map module.
	</P>
	
<H3>Fail Conditions</H3>
Fails if Key does not appear in Map.
<H3>Resatisfiable</H3>
no
<H2>See Also</H2>
<A HREF="../../lib_public/m_map/search-3.html">search / 3</A>, <A HREF="../../lib_public/m_map/keys-2.html">keys / 2</A>, <A HREF="../../lib_public/m_map/sorted_keys-2.html">sorted_keys / 2</A>
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